| Safe Haskell | Safe |
|---|
Control.Monad.MultiPass.Instrument.Counter
Description
The Counter instrument is used to generate an increasing
sequence of integers. It is particularly useful when the program
uses parallelism, because the Counter instrument creates the
illusion of a single-threaded global counter. The first pass
counts how many unique integers each thread needs so that the
integers can be generated without the use of locks during the
second pass.
- data Counter i r w p1 p2 tc
- peek :: (Num i, Monad p1, Monad p2) => Counter i r w p1 p2 tc -> MultiPass r w tc (p2 i)
- addk :: (Num i, Monad p1, Monad p2) => Counter i r w p1 p2 tc -> p1 i -> MultiPass r w tc ()
- incr :: (Num i, Monad p1, Monad p2) => Counter i r w p1 p2 tc -> MultiPass r w tc ()
- preIncr :: (Num i, Monad p1, Monad p2) => Counter i r w p1 p2 tc -> MultiPass r w tc (p2 i)
- postIncr :: (Num i, Monad p1, Monad p2) => Counter i r w p1 p2 tc -> MultiPass r w tc (p2 i)
Documentation
data Counter i r w p1 p2 tc Source
Abstract datatype for the instrument.
Instances
| Instrument tc () () (Counter i r w Off Off tc) | |
| Num i => Instrument tc (CounterTC2 i r) () (Counter i r w On On tc) | |
| Num i => Instrument tc (CounterTC1 i r) () (Counter i r w On Off tc) |
peek :: (Num i, Monad p1, Monad p2) => Counter i r w p1 p2 tc -> MultiPass r w tc (p2 i)Source
Get the current value of the counter.
Arguments
| :: (Num i, Monad p1, Monad p2) | |
| => Counter i r w p1 p2 tc | counter |
| -> p1 i | k |
| -> MultiPass r w tc () |
Add k to the counter.
incr :: (Num i, Monad p1, Monad p2) => Counter i r w p1 p2 tc -> MultiPass r w tc ()Source
Increment the counter.